How To Fix IU623 - Switch not possible for any table

IU623 - Overview

• Message type: E = Error

• Message class: IU - Incremental Conversion (ICNV)

• Message number: 623

• Message text: Switch not possible for any table

Note:
A switch is not possible for any of the tables currently in the
worklist. This could be for the following reasons:
The tables are converted within an upgrade. The switch for such tables
is automatically made in upgrade phase PRUN_RADISWTC or PCON.
The progress made when converting the individual tables is not yet
sufficient.
The tables are not currently in status 'Conversion' (see also the
status column).
See also <DS:TX.ICNV_HOWTO_5>'Switch'</>.

Error message extract from SAP system. Copyright SAP SE.

IU623 - Details

• The SAP error message IU623 ("Switch not possible for any table") typically occurs in the context of the SAP system when there is an attempt to switch a table from one state to another (for example, from a transparent table to a pooled or cluster table) but the operation cannot be completed due to certain constraints or conditions.
  Causes:
  
  Table Type Restrictions: The table you are trying to switch may not be eligible for the operation due to its current type or structure.
  Data Consistency Issues: There may be existing data in the table that violates the constraints required for the switch.
  Dependencies: Other objects (like views, indexes, or foreign keys) may depend on the table, preventing the switch.
  Technical Settings: The technical settings of the table may not allow for the switch operation.
  Database Constraints: The underlying database may have constraints that prevent the switch.
  
  Solutions:
  
  Check Table Type: Verify the current type of the table and